Gas-fired furnace



July 24, 1923. 1,463,104

W. R. TWIGG GAS AFIRED FURNAGE Filed March 29 1918 4 Sheets-Shadi wrom/f July 24, 1923. AM

- w. R. TWIGG GAS FIRED FURNACE Filed March 2.9, 1918. 4 sheets-sheet 2 July 24, 1923. 1,463,104 R. G

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1,463,104 w. R. TWIGG GAS FIRED FURNAC Filed March 2.9, 1918 4 Smeets-sheet 4 Eig. 51' @j '13,]

s 32 i 3 34 a 3 s I a A 29 y 26 2@ 3 i i 26 A- l A .WWI/l I um nl n #VvE/ww? l 79 I j, 7207553', 70- g2 7i) er l f A TT 0/7/1/5 .Patented July 24, 1923.

UNITED 4STATS PATENT OFFICE.

WALTER RATLEDGE TWIGG, 0F ,LUTONQ ENGLAND.

GAS-Fraai) FURNACE.

1 iave invented certain new and useful lmprovements, Relating to Gras-Fired Furnaces, of which the following is a specification.

This inventionvr relates to reversible regenerative gas-'fired furnaces, and has for its object to provide an improved construc-V tion of furnace which yis especially adapted for, although not limited to, use with 'coalgas and'air under pressure. lThe term coalgas is intended to denote gas obtained from the distillation of coal, with or without admixture of water gas and coke oven gas, which gas requires at least three volumes of air for itscomplete combustion, such as supplied by the statutory coal gas companies. It has heretofore been proposed to use a reversible regenerative furnace operating on coal gas, the regenerative chambers in such furnace being'situated entirely outside the .furnace structure and containing fragmentary material packed to such extent in the regenerative chambers as to necessitate rforcing the air Arequired for combustion through the said packed material-in the regenerative chambers underv pressure. p

The luse ofregenerator chambers formed entirely within the `furnace structure is known and also the simultaneous reversal of the flowl of gas and pressure air to the furnace.

According to the present inventiomvthe furnace comprises in combination, a furnace chambers formed entirely within the furnace structure, means to deliver pressure air to the regenerator chambers, means to deliver coal gas to the furnace chamber and means to reverse the. direction of the vflow of the gas and pressure air to the furnace simultaneously.

The `gas and pressure air are admitted to each side of the furnace alternately, each conduit or pipe through which the air for combustion with the gas is delivered to thel Ifurnace acting alternately as an air supply chamber.; pressure air re-genera't-or.

Application filed March 29, `1918. Serial No. 225,501.

which is divided into two parts by a par-- l tition arranged at right angles tothe gas inlets to the furnace and preferably cen-Y trally thereof, each part forming a re'gens` erative chamber for secondary air tothe furnace. A gas supply pipe is arranged'externally and on each side of the furnace,

each of which gas ,pipes delivers `gas to ya` plurality of gas inlets in eachv side ofthe furnace.

The air supply pipes are arranged out-` side and one on each side of the furnace,` each pipe supplying air to a plurality of Each regenerative chamber is.

air inlets. subdivided into two or more regenerator chambers, each pair of such chambers having a common pressure air .inlet subsequently branched vand leading vto or .connecting with the said two chambers, which are capable of supplying. a suitable volume of pressure air for fcombustonfwith the gaseous fuel issuing from one or a plurality of gas inlets. i v Manually operated means are also; .provvided yto simultaneouslyl actuate the air lcon-l trolling valve and the gas controlling valvesso as to divert the flow of gas and pressure air to the separate gas` and pressure air in 4 letson either side of the :furnace as desired, and to allow the escape of the exhaust products of combustion through the air'` pipe or pipes then yinoperative as air supply pipes to the furnace. f

I will describe with reference tothe ac-i companying drawings, constructionsin ac' cordance with 'the present inventionas air# plied to. different types of gas fired furnaces,

but I ineithervlimit myselfto the-preciseconstructions described andillustrated nor tothe types of furnaces lto which the invention may be applied;`

Figure l is a vdiagrammatic sectional-ele-l vation of a furnace present invention. p

Figure 2 is aside elevationof 4a multiple type of furnace in accordance with the present invention.

in accordance with the Figure 3 is a' sectionalV plangon theline' 3-3.Figure l Figure 4 is a longitudinal section on lthe line .t-4, Figure 3. i

vFigure 5 is a -cross 5-.45 Figure 3. V

Figures 6 and lare respectively 4'ailongh ysection Vonf the line tudinal section and a crosssection of lare-rv n.

vverheratory vtank type of `furrnice showing land 5 the pressure air inlet on the right hand side of the furnace. The gas or coal gas, as herei'nbe'fore defined, is admitted to the left hand side of the furnace by the inlety opening 6, and to the right hand side of the furnace by opening 7. The pressure air pre'- heating or regenerating chambers are indicated at 8,-9. 10 is the pressure air supply pipe leading to a controlling, valve 11,

ybranches 12, -13 being led therefrom to the pressure air preheating or regenerative chambers 8, 9. These latter chambers are connected by openings il, 5 to each side of the furnace. The gassupply pipe is indicated at 16, suitable branch' pipes 17, 18 being ledr therefrom to the left and righthand sides `of the furnace as shewn. Suitable gas controlling Avalves 19, ,are inserted in the branched gas pipes 17, 18, the spindles of the 'said gas controlling valves being connectedbyle'vers 21, 22 ft'o a common 'rod 23,r which isalso connected by a lever arm 24 to the valve spindle 'of the pressure ai'r controlling valve 11, and simultaneously operated therewith. In the present example the valve 'is shewnjas a'diamet'ric vane 11. The

levers 2-1, t22, 24 are so arranged andi connectedto the rod 23 having a manipulating handle 25, that pressure air is admitted to say the left hand side of the furnace, through the preheater or regenerator 8 and opening 4, and gas is ladmitted through the pipe 17, the admission of pressure air and gas to the right hand side ofthe furnace being completely 'shut 'off during this time. The exhaust products of combustion, pass through the lopening 5, preheating or regenerating chamber 9, pipe 13 to the valve 11 and from thence to the vfurnace chimney or flue. diterv the furnace has run for vsuch time as may be found consistent with maximum ei'ciency, as indicatedby the temperature ofthe 'exhaust products of combustion passing through the pressure air pipe acting at the particular time as an "exhaust passage, the 'admission of pressure air and gas to the left hand side of the furnace is shut off and gas is then admitted through n the valve 2() and pipe 18, and pressure; air is simultaneously admitted to the rightf hand Cases must lpaisa lthrough a preheati ordre-- kLicence.

generator beforereaching the furnace, and that each preheating or regenerating chamber 8, 9 alternately acts. as a preheating chamber and as av chamber which absorbs the heat from the exhaust products of combustion passing therethrough.

Figures 2, 3, l and 5 show the invention passages 26 through Aa built up 'or otherA A b-riekwork suitable brickwork structure. partition 27 is provided betweznil 'each jor the chambers 8, and 'a similar partition 28 between the 'chambers 9, there being a central l partition 29 between the two sets of cham bers. A. gas inlet 3l) is arranged at'ornealr the upper level of the hearth 1, the said inlet being preferably 'formed by fa tube 31 let into the structure 3 'and discharging into a suitably 'shaped space provided in 'the briclwork structure 3 adjacent the hearth 1.A

The aforesaid space 32 forms a recess, through which the whole or part of the pressure air for 'combustion from 'one regener ator or preheate'r chamber 8 .passes on its way through the 'opening 33 to the combustion chamber 2. A similar inlet 34e,4 and A also ain inlet. 35 'for the whole or part of the pressure air for combustion, are arranged in the opposite side of the furnace, The furnace is thus provided with a plurality "of gas inlets 30 onuone side, and a plurality of gas inlets y34 on the opposite side oflthe furnace, (zo-operating pressure air -inlets 33 and 35 being provided adjacent the re'spec tive gas inlets.

Preferably arranged along each side 'and outside of the furnace 'are twoT tubes -or pipes 36, v37 on one iside; "and :38, 39v on the other side of the furnace, 36 38 being 'the upper pipes'on each side and 37', the lower pipes. These pipes extend beyond the rear of the yfurnace as shewn 'more particularly in Figures 2 and 3. The pipes 36 and 38 are connected lto the gas main 40 'andthe pipes a7, 39 to the main air supply pipeu. In the vconstructien shown, Ithe `vlofwer pipes 39 are'conn'ected by a common cross ,pipe 42 provided ywith a valve,`hereinbefore referred.

to as A11, 'for 'controlling the supply 'of the whole or part of `the 'pressure air for coinbustion, and the yescape l'of fthe 4reliaust 'or waste lgases from `thel furnace which gases` pass fthroughfone or other o'f th'e lower pipes a7, 39 t@ rhefchiimiey .flue "59.

Secured at intervals to, and along the length of each pipe 36 and 38 are a number of gas burners 47 of the Bunsen or othersuitable type, the nozzle 48 of each burner being arranged below, and if desired projecting into, the flared end of a tube 49 leading to thegas inlet tube 31, let into and suitably supported inl the'wall. of the furnace struc-ture, the continuity of the connections for the gas supply from the pipes 36, 36 to the burners being thus interrupted or broken, The several burners 47 on each side of the furnace are preferably provided with valves 50 arranged between the branched gas supply pipes 36, 38 (not the main gas supply pipe), and the nozzle 48 from which thevgas issues into the iared tube 49, into which air may be induced by the gas issuing from the burner nozzles 48.

The lower pipes 37, 39 may be arranged at any convenient level, and from these pipes which are plugged or closed at their front ends, branch pipes 51, 52 are led to the several preheating or regenerating chambers below the furnace hearth. The inlet passages 53 for pressure air to each of the preheating or regenerating chambers 8, 9' may if so desired be forked or branched as shewn at 54, 55, Figure 3, after passing through the furnace wall 3, the two passages being separated by a` partition 56 of brickwork having if desired",y suitable openings therein and arranged at intervals in the height of the partition.

In the construction shewn in Figures 2, 3, 4 and 5, a plurality of preheating or regenerating chambers are preferably employed, these chambers being situated below the hearth 1 and arranged in sets of four, two sets of two separate or 4communicating chambers 8, 9 on each side of the partition 29 arranged centrally, and extending longitudinally of the furnace. There are thus two preheating chambers on each side of the central partition 29, each chamber having a separate pressure air inlet, which is subsequently branched as already stated to admit through passages 54 and 55 the necessary volume of. pressure air for combustion.

Each chamber 8 and 9 has thus two 'inlets ing from the gas main 40, and between the last burners ofthe gas burners 4.7 on each of the upper pipes 36, 38 and the gas supply main.

The three valves, .iviz, the pressure air-` controlling valve 11, and the gascontrolling valves 19 and 2O canthus be simultaneously controlled so as to` direct the pressureV air and gas to say the*- left` hand sections `of the furnace for any desired length of the time, whilstclosing.the-admission of pres-- sure air and gas to the right hand sections of the furnace. Duringthis period, the eX- haust products ofcombustion or thewaste gasesiescape'through the pressure air.y inlet openings 35 on thel right hand side of the furnace, and from thenceA by the preheater or regenerator chambers 9, pipe 39, pipe 42, valve lliand` pipe 58, tothe chimney ory flue 59. `The relative positions of the three valves 11, 19 and 20 are then altered by operating the rod 23 so as to close the admisrsion of gas yand pressure air to the left hand section ofthe furnace, whilst at the same timeadmitting pressure air and gas to the right hand section lof the furnace. The exhand section of the furnace escapethr'ough the pressure air inlets or openings 33, `the preheater or 'regenerator chambers 8, pipe' 37, pipe 42, valve 11 and pipe 58 'to' the furnace chimney ory flue 59. The side at which combustion takes place isthen reversed or changed to the left hand side of the furnace, and the reversible 'action is continued as longas desired, using producergas, or coal gas as hereinbefore defined, or other suitable permanent gasas afuel, and pressure air for'combustion. "In the construction shown in Figures 6 and 7, the hearth is indicatedby the refen ence numeral 1,' and the combustion chamber by 2. The furnacewalls are indicated generally by the reference 3. The preheating or regenerating chambersare-shewn at 8 and 9 and the pressure airvalve at 11. The gas controlling valve shown at 69 `is somewhat similar to the pressure air c-ontrolling valve 11, in that the said valve isk adapted to control both'gas inlets to the furnace, theV diametrically'arranged varies 70, 71 ofthe pressure air valve and the gas controlling valve respectively being `reversely `disposed vas shewn. 72 is the pressure air sup-ply pipe, andv 73 the gas supply pipe.- The pressure air controlling valve casing is provided with oppositelyl disposed outlets leading by the pipes74and`75 to opposite sidesfo'f the furnace and opening into the combustion chamber2 above the gas inlets 76, 77, to. whichga'sgis supplied from the main 73, through the valve lcasimgf) and pipes 78. 79, j p

-The method of operating this type of furnace is the same as described with reference to the other -iigures of the drawings. The furnace is started up iin anyv suitable man;v

asto close the admission of pressure airand gas through the inlets 8O and 76. lThe gas pressure and air is fthus diverted so 5 as to flow' through the inlets' `7-7 and 81. at the right hand side of the furnace, the vproducts of combustion or Waste gases passing by the opening- 80 preheating or regenerating chamber 8 pipe 74, valve 11 and pipe f82to the furnace. flue or chimney.k Thevpreheating or regenerating chambers 8,9 thus respectively act simultaneously, one, 8 to heat the in* coming pressure air tothe furnace, and the. other, 9, to absorb heat vfrom the products of combustion or Waste gases passing through the said chamber 9,. Gn-reversal, the chamber 9 heats the incoming pressure air and the chamber Sabsorbs the heat from the products ofcombustion or Waste gases passing therethrougl-i.y i Y If desi-red bypass vconnections 88, Figure 2 may be provided between themain'air supply pipe` and the gas branch supply pipes, .suitable valves vSet being pro-vided for controlling the admission of by-Ipass air to the gas supply pipes which lby-passair may form the primary air for combustion. -Y `Such by-pass connections may be arranged to deliver yprimary air'- -in :parallel as at 83, or

separately as at 85 fto each individual burner. The air-by-pass valves, main air controlling valve and gas valves may be simultaneously I j controlled.- 1

Thevbr-iclnvork structure forming the-secs tional furnace vhereinbefore vdescribed may be'strengthened by H .beams and channel 'beams yand tie rods or `other members of suitable section. y v

1. A reversi-ble regenerative furnace comprising a furnace structure having a hearth, pressure air re-generator chambers provided underneath the said/hearth and .Within the furnace structure, means to deliver lpressure air to the r'egenerator chambers, -means to; deliver coal fgas to the furnace combustion chamber, openings -in the furnace hearth adjacent the outlet end ef .the gas deliverT ing means to permit admiXture of air and gas for combustion, .and means' to eifect reversal of the directiony of lthe :flow of the gas and air.

f 2. A reversible regenerative gas' firedfur nace, comprising, fiincoginbinatiom `a combustion' chamber, pressure ,fair iregenerater Chain. here entirelycvvithin "the furnace structure,-

ineaioa afsupply pipe for vgas on each sidev cf the :furnace and exterierthereof, apressure air supply pipe on each side of the furnace and exterior thereof, a plurality of separate vgas inlet passages leading from each gas pipe to the adjacent part of the combustion cham? ber, aplurality'of separate pressure air inlet passages leading from each pressure air pipe to the adjacent regenerator chamber, means to reverse the direction of {ioW-of the gas and airi from one side of the furnace chamber tothe opposite side, each air inlet pipe acting alternatelyv as an air supply passage coinmon to all the gas inlets then in action, land upon reversing the flovvof the gas and airv acting as a fluel or passage for the escape'of the exhaust products of combusticn to the chimney or furnace iiue.

y3. A reversible regenerative .gas-'firedfurnace, comprising, in combination, a combustion chamber, a. chamber underneath the hearth divided into two `parts by a partition, each part communicating by an opening with the `combustion chamber and each part ef said chamber forming a regenerator chamber for secondary air .to the furnace, gas inlets leading into the combustionV chamber ateach side above said openings, a gas supply pipe arranged externally of said furnace andvfeeding said gas inlets, air'supply pipes arranged eXte-rierlyof said furnace and connecting with the bttom of each part of said chamber, each air supply pipe acting alteijnatelyfas apipe for supplying air only and as an exhaust pipe for the escape of the exhaust vproducts of combustion to -the chiiiiiieyfflue.y f y 4L. A reversible regenerative gas fired fur! nace comprising a furnace structure having a hearth anda combustion chamber, pres-r i sure air regeneratcr chambers provided underneath said hearth andvvitliin the fui'-l nace structure, each regenerator chamber be. ing divided by a transverse partition to form two separate regenerator chambers, mea-nato.v deliver pressureair to the regenerator chambers, means to deliver coal gas to. the Afurnace combustionchamber, Iopen'-r vings inthe furnace hearth to permit admi);-

ture of air `and gas for combustion, and means to effect reversal of the direction of the iioiv ofthe gasfand air.

ico

`, i is 5. 'A reversible regenerative gas fired fun.

nace', comprising, in combiiiation,y a coinbustion chamber. a chamber underneath the furnace hearth divided by a partition into tivo parts, eachpart being sub-divided into tvvo or more regenerator chambers, gas inlets leading intof the combustionchamber at `each side, a gas supply pipe larranged .eX- ternallyof saidfurnace and feeding. said gas inlets,'ai-r supply pipes arranged 'eX- teriorly of said furnace, each pair ,of such chambers having a commonpressure air inlet capable of supplying @suitableveluine'cf ificalc@c of separate pressure air inlet passages lead-` ingfrom each pressure air supply pipe to the adjacent regenerator chamber, by-pass connecting pipes between the main air supply pipe and the gas branch lsupply pipes, means to control the admission of by-pass air to the gas supply pipes in parallel or individually as desired, and means to reverse the direction of flow of the gas and air from one side of the furnace chamber to the opposite side.

7. A reversible regenerative gas fired furnace comprising in combination separate gas and pressure air inlets on each side of the furnace, a plurality of regenerator chambers below the furnace hearth arranged in pairs on each side of the longitudinal central line of the furnace, loosely packed or ehequered hre bricks disposed in each regenerator chamber, a partition dividing each regenerator chamber into compartments, an air pressure inlet common to two of said compartments, branched passages leading from the common pressure air inlet and connecting the saine with the compartments, means to supply and deliver pressure air to and through said compartments to the air inlets to the furnace and means to reverse the direction of flow of the gas and pressure air simultaneously.

8. A reversible regenerative gas tired furnace, comprising, in combination, a

combustion chamber, a hearth, pressure air:

regenerator chambers formed entirely within the furnace structure below the hearth and divided into two parts, each having an opening communicating through the lhearth with the combustion chamber, a gas supply pipe for coal gas exterior thereof, a pressure air supply pipe exterior thereof, a plurality of gas inlets connecting with the gas supply pipe and delivering gas to the combustion chamber on each side thereof, a plurality of separate pressure air inlet passages leading` from the pressure air supply pipe to each of the regenerator chambers at the bottom thereof, and means to reverse the direction of flow of the gas and pressure air to the furnace.

9. A reversible regenerative gas fired generatorchainbers formed entirely within the furnace below the hearth and communicating by openings through the hearth with each side of the combustion chamber, a gas supply pipe for coal gas on each side of the furnace and exterior thereof, a pressure air supply pipe on each side of the furnace and exterior thereof, a plurality of separate gas inlets leading from-each gas pipe to the combustion chambers on opposite sides of the furnace, a plurality of separate pressure air inlet passages leading from each pressure air pipe to the adjacent regenerator chamber below the hearth, and means to simultaneously reverse the direction of flow of gas and air from one side of the furnace chamber to the opposite side, whereby one of the regenerator chambers acts simultaneously and alternately to heat the incoming pressure air to the furnace while the other absorbs heat from the products of combustion passing therethrough to the stack. F

l0. In a reversible regenerative gas fired furnace, the combination of a combustion chamber, a hearth, a partition supporting the hearth and disposed centrally thereof, a regenerator chamber on each side of the hearth and in communication with the combustion chamber but out of communication with each other, means to deliver pressure air separately to said regenerator chambers, means to deliver coal gas to the .combustion chamber, and means to effect reversal of the direction of the flow of the coal gas and pressure air from one side of the combustion chamber to the opposite side.

1l. A reversible regenerative gas fired furnace comprising in combination a furnace structure, a hearth within 'said structure, pressure air regenerator chambers under `said hearth and within the furnace structure, means to admit pressure air to each regenerator chamber, said means also acting to permit the escape of the products of combustion through said regenerator chamber, a gas supply pipe on each side `of the furnace and exterior thereof, a plurality of separate Vgas inlet passages leading from each gas pipe to the adjacent part of the combustion chamber, a plu.

WALTER RATLEDGE TWIGG. 

